Roller assemblies for the pressure treatment of materials



July 10, 1962 v. APPENZELLER 3,043,211

ROLLER ASSEMBLIES FOR THE PRESSURE TREATMENT OF MATERIALS Filed April22, 1959 a United States Patent 3,943,211 Patented July 10, 1952 ROLLERASSEMBLIES FOR THE PRESURE TREAIIWENT OF MATERIALS Valentin Appenzeller,Krefeid, Germany, assignor to Eduard Kiisters, Krefeld, Germany FiledApr. 22, 1959, Ser. No. 808,080 Claims priority, application GermanyApr. 24, 1958 4 Claims. (Cl. 100-170) This invention relates toimprovements in roller assemblies for the pressure treatment ofmaterials such as the smoothing and embossing of paper and othermaterials, for the squeezing out of moisture from textiles, for thecalendering and drawing out of sheets of plastic and rubber and the likeas well as for pressing applications in which the roller consists of adrum or tube-like cylinder adapted for rotation and also forming theroller periphery and a stationary core for taking the load locatedtherein whereby there is a pressure means acting on the inner surface ofthe cylinder and packings lying on the inner surface of the cylinder aswell as on the core for preventing an overflow of the pressure mediumfrom the operative side of the core.

The known rollers for the pressure treatment of material webs oncarrying out work undergo bending on the non-operative side, i.e. theside away from the operative portion of the roller which adverselyaffects the uniform pressure on the whole length of the roller when theroller is pressed via its journals against a counter roller or asupport.

Various proposals are already known for obviating this drawback. Thus acurved roller has been proposed. Here there is the drawback that everycurvature can only take into consideration a certain pressure wherebyfor every pressure another roller is necessary.

It has also been proposed to subject the operating roller or rollers tofluid pressure in which the rollers are formed with a core and dividingplates for defining the fluid chamber to which fluid under pressure isadmitted and pressure is applied to the ends of the top roller throughpistons acting thereon.

According to the invention a tubular roller is mounted to enclose arelative floating core, and to provide a gap between the inner peripheryof the tubular roller and the core, an inflated member being providedbetween the core and the tubular roller over the portion of theperiphery subjected to pressure contact.

The invention will be described with reference to the accopanyingdiagrammatic drawings:

FIG. 1 shows a roller in cross section.

FIG. 2 illustrates in longitudinal section the additional pressure onthe journals of the roller core.

The roller or rollers co-operating with the roller 1 shown are notillustrated. The roller 1 consists of a tubular hollow body which needonly have a comparatively thin wall thickness and may consist ofsuitable material such as steel, flexible or elastic material, syntheticmaterial such as, for example, polyamide and superpolyamide. The hollowbody 1 is arranged on a stationary rigid core 3, for example, of steelmounted in the machine stand, not shown. The core 3 is of circular crosssection and provides around its whole periphery a gap 4 between thehollow cylinder 1. A portion of the core 3 shown in the drawing as onthe underside, is reduced to a smaller diameter. An inflatable member 21of suitable material such as rubber, elastic synthetic material or thelike isarranged in the reduced portion of the core 3. The inflatablemember is filled with a pressure medium and bears against the innerperiphery of the hollow cylinder 1. A bearin sheet 22 is arrangedbetween the inner periphery of the hollow clinder 1 and the inflatablemember 21.

As shown in FIG. 2 the journals 23 of the core 3 are under pneumatic orliquid pressure which is exercised via pistons located in the cylinders24. The cylinders are connected to one another via a common pipe 25 andare connected to a compressed air source 27 or liquid pressure sourcevia the pipe 26. The inflatable member 21 is also connected via the pipe28 to this compressed air or liquid pressure source. In the pipes 26 and23 regulating valves 29 and 34 are located which permit of theadjustment of the pressure in the inflatable member 21 and in thecylinder 24 so that these pressures bear a predetermined relation to oneanother.

The roller 1 exercises on its whole length a uniform pressure on acounter-roller or other support as the pressure of the liquid located inthe inflatable member body is transmitted uniformly on all sides withoutrequiring other means to ensure the uniform exercising of the pressure.Any deflections of the stationary core have no influence on thesatisfactory contact of the tubular roller on the roller in contacttherewith;

The pressure medium may be located in the inflatable member 21 sealed onall sides so that on operation of the roller by the reaction pressurecaused by the material web to be treated it is placed under pressure.The inflatable member 21 may however be connected to a separate pressuresource as, for example, to an air cylinder to which pressure regulatingvalves are provided in order to be able to eiiect a selective adjustmentto a predetermined pressure to be maintained.

The core 3 forming approximately a circular surface in cross section isreduced in diameter on the operative side to form a recess for receivingthe inflatable member 21. By the contact of the inflatable member 21 ona cylindrical core surface the inflation body is protected as much aspossible against damage.

The inflatable member 21 bears against a bearing sheet on the innerperiphery of the hollow roller 1. The friction reducing bearing sheetprotects the inflatable mem-.

ber 21 on this side from wear and facilitates the rota tion of theroller 1. The bearing sheet may be made of synthetic material such as ofpolyamide or superpoly amide or of bronze.

One advantage of the invention consists of the fact that the roller 1may be employed as a lower roller instead of as an upper roller. Rollersconstructed according to the invention may be employed with otherrollers as upper rollers or as lower rollers.

The reduction of the possibility of bending of the tubular roller 1 inits centre portion under the influence of the pressure medium iseffected since a greater controlled pressure is exercised in relation tothe ends of the roller in that the pressure is maintained in thedirection of the counter roller, for example by pneumatic means on thejournals of the roller core. This is of particular advantage if withpressure treatment mechanisms with long rollers narrow web materials areto be treated. The optimum pneumatic pressure on the journals 23 and thepressure via the inflatable member 21 can be brought into predeterminedrelationship with one another by means of a differential regulator sothat there are, for example, uniform pressures along the whole length ofthe roller. If the pressure on the journals is reduced then the rollerbends in the middle and acts like a curved roller without howeverbecoming larger in diameter or in the central portion.

What I claim is:

1. A roller assembly for the application of pressure to surfaces forcalendering, drawing and rolling, said roller assembly including aroller having a tubular rotar" cyl inder, an elongated stationary rigidcore substantially coaxial therewith, said core being mounted within andco-,

extensive with said cylinder, said coreibeing spaced from the innersurface of said cylinder, and an arcuate shaped stationary inflatablemember mounted on said core to fill a portion of the space between saidcore and the inner surface of said cylinder, said inflatable memberbeing substantially coextensive in length with said cylinder so asproduce a continuous uniform pressure along substantially the entirelength of said cylinder.

2. A roller assembly according to claim 1 wherein said coreisrecessed-around a portion of its periphery to reiceive said inflatablemember.

3. A roller assembly according to claim 1 including a bearing sheetdisposed between said inflatable member and said rotary cylinder. a

4. A roller assembly according to claim 3 including p I 4 A journals onthe ends of said core, and fluid supply means for applying fluidpressure to both said journals and to said inflatable member, said fluidsupply means including a fluid supply line=having a valve therein tomaintain 'a predetermined relationship between the pressure to saidjournals and to said inflatable member.

References Citedin the file of this patent UNITED STATES PATENTS GermanyJan. 4, 1934 Mann. 1

